Unlock instant, AI-driven research and patent intelligence for your innovation.

Thermal protector

Active Publication Date: 2010-12-09
UCHIYA THERMOSTAT
View PDF49 Cites 9 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0025]An object of the present invention is to provide, in light of the above described conventional circumstances, a thermal protector including a polymer PTC in a safe state where a hot spot does not occur even if a volume is expanded by a thermal expansion at the time of heat production.
[0031]The thermal protectors according to the first and the second inventions further comprise for example an insulative member that is provided at a position further inward than an insulative filling material for sealing an opening of the main body housing of the thermal protector and further outward than the resistive element, and that prevents the insulative filling material from intruding deeper.
[0033]The thermal protectors according to the first to the third inventions are characterized in that the resistive element effectively functions also as a polymer PTC (Positive Temperature Coefficient).
[0034]As described above, according to the present invention, a terminal member connected to one of the electrodes on both surfaces of a plate-shaped PTC is fixed to a fixed side of a movable plate, and a terminal member connected to the other electrode is configured to be able to fluctuate within the range of a thickness that has been increased by a thermal expansion of the FTC. As a result, a self-hold type thermal protector where the PTC effectively functions as a polymer PTC as well can be provided.

Problems solved by technology

Therefore, the structure of the PTC conductive polymer device that is illustrated in FIG. 5 and disclosed by Patent Document 1 is not applicable to a self-hold type.
Therefore, the degree of freedom of the volume expansion caused by the thermal expansion of the polymer PTC at the time of heat production is hindered, leading to an inevitable occurrence of the above described hot spot.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Thermal protector
  • Thermal protector
  • Thermal protector

Examples

Experimental program
Comparison scheme
Effect test

first embodiment

[0134]FIG. 1A is a perspective view illustrating a resistive element module used in a thermal protector according to a FIG. 1B is a top view of the resistive element module. FIG. 1C is a side sectional view of the resistive element module. The resistive element module 60 illustrated in FIGS. 1A, 1B and 1C is composed of a polymer PTC 61, a first terminal member 63, and a second terminal member 64.

[0135]In this embodiment, the polymer PTC 61 as a resistive element is composed of an internal resistor 62, and thin-layer electrodes 62a and 62b are respectively pasted onto upper and lower surfaces of the internal resistor 62. The entire polymer PTC 61 is formed in the shape of a plate.

[0136]Onto one electrode 62b of the electrodes positioned on the upper and the lower surfaces of the internal resistor 62, a first terminal member 63 is pasted. For the first terminal member 63, a movable contact side external connection terminal part 63-1 that outwardly protrudes from the surface pasted o...

second embodiment

[0171]A thermal protector is described next.

[0172]FIG. 3A is a perspective view illustrating a resistive element module used in the thermal protector according to the second embodiment. FIG. 3B is a top view of the resistive element module. FIG. 3C is a side sectional view of the resistive element module. The resistive element module 85 illustrated in FIGS. 3A, 3B and 3C is composed of a polymer PTC 86, a fixed contact side terminal member 87, and a movable contact side terminal member 88.

[0173]In this embodiment, the polymer PTC 86 as a resistive element is composed of an internal resistor 89 and thin-layer electrodes 89a and 89b respectively pasted onto upper and lower surfaces of the internal resistor 89. The entire polymer PTC 86 is formed in the shape of a plate.

[0174]A middle part of the fixed contact side terminal 87 is pasted onto the entire surface of the electrode 89a of the internal resistor 89. On the fixed contact side terminal 87, a fixed contact 91 is formed at an en...

third embodiment

[0197]Another configuration that does not hinder the degree of freedom of the volume expansion caused by the thermal expansion of the internal resistor of the resistive element module is described below as a

[0198]FIG. 4A is an exploded perspective view of an internal configuration of a thermal protector according to the third embodiment, whereas FIG. 4B is a side sectional view of the assembled thermal protector. FIG. 4B is a sectional view of the thermal protector sectioned at the support column 112 of FIG. 4A in the horizontal direction (from an obliquely lower left section toward an obliquely upper right section in FIG. 4A).

[0199]As illustrated in FIG. 4A, the internal configuration of the thermal protector according to this embodiment is composed of a movable contact side terminal 106, a bimetal 107, a movable plate 108, a spacer 109, a resistive element module 110, a fixed contact side terminal 111, and a support column 112.

[0200]As illustrated in FIGS. 4A and 4B, an installati...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

A movable contact of a movable plate rises and separates from a fixed contact when a bimetal of the thermal protector inversely warps at a predetermined temperature, an electric current between the contacts, namely, an electric current between a movable contact side terminal and a fixed contact side terminal is disrupted, and the disrupted current flows into the polymer PTC, which is then made to produce heat and is thermally expanded to increase a resistance value. A second terminal member on a side opposite to a first terminal member where the polymer PTC is positioned and fixed forms a bowing part, and a gap is formed between an upper inner wall of a housing and the second terminal member.

Description

TECHNICAL FIELD[0001]The present invention relates to a thermal protector for preventing a temperature of an electric product from rising too high, and more particularly, to a thermal protector in which a polymer PTC is embedded in a safe state where a hot spot does not occur.BACKGROUND ART[0002]Conventionally, a self-hold type thermal protector including a ceramic PTC (Positive Temperature Coefficient) connected in parallel with a contact circuit is used as a device for preventing a temperature of an electric product from rising too high.[0003]Such thermal protectors are intended to mainly prevent a temperature of an electric product using a commercial power supply from rising too high, and some thermal protectors control a disruption of an electric current of a voltage as high as 100 to 200V.[0004]However, in some thermal protectors, a ceramic PTC is used as a device for preventing a temperature from rising too high even in an area using an electric current of a low voltage such a...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): H01H37/46
CPCH01H37/32H01H37/46H01H37/043H01H37/5418
Inventor TAKEDA, HIDEAKI
Owner UCHIYA THERMOSTAT